Test device

ABSTRACT

A test device for a high-speed/high-frequency test. The test device includes: a conductive block which includes a probe hole; at least one signal probe which is supported in an inner wall of the probe hole without contact, includes a first end to be in contact with a testing contact point of the object to be tested, and is retractable in a lengthwise direction; and a coaxial cable which includes a core wire to be in electric contact with a second end of the signal probe. With this test device, the coaxial cable is in direct contact with the signal probe, thereby fully blocking out noise in a test circuit board.

REFERENCE TO RELATED APPLICATIONS

This is a divisional of pending U.S. patent application Ser. No.16/850,116 filed on Apr. 16, 2020, which is a continuation ofInternational Patent Application PCT/KR2018/014396 filed on Nov. 22,2018, which designates the United States and claims priority of KoreanPatent Application No. 10-2017-0162775 filed on Nov. 30, 2017, theentire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present disclosure relates to a test device, and more particularlyto a test device for a high-speed and high-frequency test, whicheffectively blocks out noise from an adjacent signal line and isexcellent in signal transmission characteristics.

BACKGROUND OF THE INVENTION

To test electric characteristics of an object to be tested such as asemiconductor, a test device has employed a probe socket for supportinga test probe, and a test circuit board for contacting the test probe andapplying a test signal. As a high-frequency and high-speed semiconductoris decreased in pitch and increased in allowable current, a noise shieldbetween signal probes of the probe socket has become very important.That is, the mechanical length, impedance matching, etc. of the testcircuit board have become important as test speed and frequency gethigher.

A conventional test device includes a probe socket for supporting asignal probe, and a test circuit board placed under the probe socket andproviding a test signal. The probe socket performs a test as the signalprobe is inserted in a conductive brass block without contact. Further,the test circuit board includes a signal pad and a conductive columnformed on an insulating dielectric substrate and transmitting the testsignal. When the high-frequency and high-speed semiconductor or the likeobject that requires high isolation is subjected to the test, aconductive ground body has been used to shield adjacent signal probes ofthe probe socket from each other. However, for a more reliable test,there is a need of managing an isolation loss caused by noise madebetween the conductive columns and between the signal pads of the testcircuit board. Further, the test circuit board includes a wiring linehaving a predetermined length, and thus a signal loss is causedcorresponding to the length of the wiring line, thereby deterioratingsignal transmission characteristics.

SUMMARY OF THE INVENTION

An aspect of the present disclosure is conceived to solve theconventional problems, and provides a test device which effectivelyblocks out noise between adjacent signal lines and tests ahigh-frequency and high-speed semiconductor excellent in transmissioncharacteristics of a test signal.

In accordance with an embodiment of the present disclosure, there isprovided a test device. The test device includes: a conductive blockwhich includes a probe hole; at least one signal probe which issupported in an inner wall of the probe hole without contact, includes afirst end to be in contact with a testing contact point of the object tobe tested, and is retractable in a lengthwise direction; and a coaxialcable which includes a core wire to be in electric contact with a secondend of the signal probe. Thus, the test device certainly blocks outnoise between the signal probes on a cable supporting substrate andenhances the transmission characteristics of the test signal.

The test device may further include a cable accommodating hole in whichthe coaxial cable is accommodated, and a cable supporter which includesa cable supporting block coupled to the conductive block so that theprobe hole corresponds to the cable accommodating hole, thereby firmlysupporting the coaxial cable.

The cable supporting block may include a cable supporting recess forsupporting the coaxial cable, thereby preventing the coaxial cable frommoving.

The cable supporter may include an extended plate portion integrallyextended from the cable supporting block, thereby preventinginterference between the coaxial cables.

The cable supporter may include a cable supporting substrate having athrough hole through which the cable supporting block passes, therebystably fastening the cable supporting block to the conductive block.

With this test device, the coaxial cable is in direct contact with thesignal probe, thereby fully blocking out noise in a test circuit board.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will become apparent and more readilyappreciated from the following description of exemplary embodiments,taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an exploded cross-sectional view of a test socket in a testdevice according to a first embodiment of the present disclosure;

FIG. 2 is a plane view of the test device according to the firstembodiment of the present disclosure;

FIG. 3 is a bottom perspective view of the test device according to thefirst embodiment of the present disclosure;

FIG. 4 is an exploded perspective view of the test device according tothe first embodiment of the present disclosure;

FIG. 5 is a cross-sectional view of the test device according to thefirst embodiment of the present disclosure;

FIG. 6 is a partial enlarged cross-sectional view illustrating adetailed coupling state between a signal probe and a coaxial cableaccording to the first embodiment of the present disclosure; and

FIG. 7 is a cross-sectional view of a test device according to a secondembodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Below, a test device 1 according to a first embodiment of the presentdisclosure will be described in detail with reference to theaccompanying drawings.

FIG. 1 is an exploded cross-sectional view of a test socket in the testdevice 1 according to a first embodiment of the present disclosure, andFIGS. 2 to 6 are respectively a plane view, a bottom perspective view,an exploded perspective view, a cross-sectional view and a partialenlarged cross-sectional view of the test device 1 according to thefirst embodiment of the present disclosure. As shown therein, the testdevice 1 includes a test socket 100, a coaxial cable 200, and a cablesupporter 300.

Referring to FIG. 1 , the test socket 100 includes a conductive block110 having at least one signal probe hole 112 and at least one groundprobe hole 114; a signal probe 120 contactless-accommodated in thesignal probe hole 112; a ground probe 130 contact-accommodated in theground probe hole 114; an upper supporting member 140 for supporting anupper end of the signal probe 120, and a lower supporting member 150 forsupporting a lower end of the signal probe 120.

The conductive block 110 includes an upper supporting memberaccommodating groove 116 on an upper side to accommodate the uppersupporting member 140. The upper supporting member accommodating groove116 includes a shield island 117 protruding at the center. The shieldisland 117 blocks out noise made in the signal probes 120 supported onthe non-conductive upper supporting member 140. The signal probe 120 inthe middle passes through the signal probe hole 112 without contact, andis then supported on the upper supporting member 140.

The signal probe 120 has an upper end to be in contact with a testingcontact point (not shown) of an object to be tested, and a lower end tobe in contact with a core wire 210 of the coaxial cable 200. The signalprobe 120 applies a test signal through the core wire 210 of the coaxialcable 200. The signal probe 120 may be materialized by a retractablePogo pin. The signal probe 120 includes a barrel (not shown), upper andlower plungers (not shown) partially inserted in the opposite ends ofthe barrel, and a spring (not shown) arranged between the upper andlower plungers within the barrel. At least one of the upper and lowerplungers is inserted in the barrel and slide to compress the springwithin the barrel.

The ground probe 130 having an upper end to be in contact with a groundterminal of an object to be tested (not shown), and a lower end to be incontact with the cable supporter 300. The ground probe 130 receives aground signal from the object to be tested. The ground probe 130 may bemay be materialized by a retractable Pogo pin. The ground probe 130includes a barrel (not shown), upper and lower plungers (not shown)partially inserted in the opposite ends of the barrel, and a spring (notshown) arranged between the upper and lower plungers within the barrel.At least one of the upper and lower plungers is inserted in the barreland slide to compress the spring within the barrel. The ground probe 130is supported being in contact with the conductive block 110.

Referring to FIG. 1 and FIG. 2 , the shield island 117 is interposedamong three signal probe 120, and five ground probe 130 are supportedbeing in contact with the shield island 117. In result, the groundedshield island 117 shields the signal probes 120 from noise.

The upper supporting member 140 is fastened to the conductive block 110by a first screw 142 as accommodated in the upper supporting memberaccommodating groove 116, thereby supporting the signal probe 120. Thesignal probe 120 is inserted in the signal probe hole 112 of theconductive block 110 without contact as floating to prevent ashort-circuit. To this end, the insulating upper supporting member 140supports the upper end of the signal probe 120.

Similarly, the lower supporting member 150 is made of a conductivematerial and is accommodated in a lower supporting member accommodatinggroove 118 to support the lower end of the signal probe 120. The signalprobe 120 is inserted in the signal probe hole 112 of the conductiveblock 110 without contact as floating to prevent a short-circuit. Thelower supporting member 150 includes an insulating signal probesupporting member 152 to support the lower end of the signal probe 120.In result, the signal probe 120 passes through the conductive block 110and the lower supporting member 150 without contact, and the oppositeends of the signal probe 120 are supported by the upper supportingmember 140 and the signal probe supporting member 152.

The signal probe hole 112 and the ground probe hole 114 are formedpenetrating the upper supporting member 140, the conductive block 110and the lower supporting member 150. The signal probe 120 is inserted inthe signal probe hole 112 without contact, and the ground probe 130 isinserted in and contacts the ground probe hole 114. In this case, bothends of each of the signal probe 120 and the ground probe 130 partiallyprotrude from the top and bottom surfaces of the upper supporting member140 and the conductive block 110.

The coaxial cable 200 includes a core wire 210 placed at the core andtransmitting a signal, an external conductor 220 surrounding the outerportion of the core wire 210 as separated from the core wire 210 toblock out the noise, and an insulator 230 filled in between the corewire 210 and the external conductor 220. The core wire 210 of thecoaxial cable 200 is grinded for contact with the signal probe 120. Thecoaxial cable 200 has a first end contacting the signal probe 120 andsupported on a cable supporting block 310 (to be described later), and asecond end supported on a cable supporting substrate 320 positioned asseparated from the first end. The coaxial cable 200 includes a signalconnector 240 to receive a test signal from the outside. The signalconnector 240 is mounted to the cable supporting substrate 320.

The cable supporter 300 includes the cable supporting block 310 having acable accommodating hole 312 for accommodating the coaxial cable 200,and the cable supporting substrate 320 mounted with the test socket 100.

The cable supporting block 310 includes a plurality of cableaccommodating holes 312 at positions corresponding to the signal probeholes 112 of the lower supporting member 150. The cable supporting block310 may be made of conductive metal. The cable supporting block 310 iscoupled to the conductive block 110 by a second screw 144 as inserted ina through hole 322 of the cable supporting substrate 320. The cablesupporting block 310 includes a cable supporting recess 314 (see FIG. 6) which is recessed from a surface opposite to an area where the cablesupporting block is coupled to the conductive block 110, and an extendedplate portion 316 extended transversely. The coaxial cable 200 isinserted in the cable accommodating hole 312 of the cable supportingrecess 314 and secured in place with adhesive (or glue) 315 filled inthe cable supporting recess 314 and hardened. The extended plate portion316 is in contact with a rear side of the cable supporting substrate 320and supports the cable supporting substrate 320 along with the testsocket 100.

The cable supporting substrate 320 includes one side onto which the testsocket 100 is mounted, and the rear side to which the second ends of thecoaxial cables 200 are separately attached for blocking out the noise.The cable supporting substrate 300 includes the through hole 322 inwhich the cable supporting block 310 is accommodated while penetratingthe cable supporting substrate 300.

FIG. 7 is a cross-sectional view of a test device 2 according to asecond embodiment of the present disclosure. In comparison with the testdevice 1 described with reference to FIGS. 1 to 6 , like numerals referto like elements, and only different parts will be described.

As shown therein, the test device 2 includes the test socket 100, thecoaxial cable 200, and the cable supporter 300.

The cable supporter 300 does not include the cable supporting substrate320 unlike that of the first embodiment, and the signal connector 240 isfastened to the extended plate portion 316 instead of the cablesupporting substrate 320.

In the test device according to the present disclosure, the signal probesupported in the conductive block is in direct contact with the corewire of the coaxial cable, thereby certainly blocking out the noisebetween the signal lines at a side of an test circuit board andimproving the transmission characteristics of the test signal. Thus, thetest device according to the present disclosure enhances the testreliability at a high-speed/high-frequency test.

Although the present disclosure is described through a few exemplaryembodiments and drawings, the present invention is not limited to theforegoing exemplary embodiments and it will be appreciated by a personhaving an ordinary skill in the art that various modifications andchanges can be made from these embodiments.

Therefore, the scope of the present disclosure has to be defined by notthe exemplary embodiments but appended claims and the equivalents.

What is claimed is:
 1. A test device for testing electriccharacteristics of an object, the test device comprising: a conductiveblock including at least one signal probe hole for accommodating atleast one signal probe therein without contacting an inner wall of thesignal probe hole, and at least one ground probe hole for accommodatingat least one ground probe therein while allowing contacting an innerwall of the ground probe hole; an upper supporting member mounted on anupper surface of the conductive block, the upper supporting memberincluding at least one signal probe hole at locations corresponding tothe at least one signal probe hole of the conductive block, the signalprobe hole of the upper supporting member being configured to support anupper end of the signal probe introduced thereto through the signalprobe hole of the conductive block; a lower supporting member mountedunder a lower surface of the conductive block, the lower supportingmember including at least one signal probe hole at locationscorresponding to the at least one signal probe hole of the conductiveblock, the signal probe hole of the lower supporting member beingconfigured to support a lower end of the signal probe introduced theretothrough the signal probe hole of the conductive block; a coaxial cableincluding a core wire configured to be in electric contact with thelower end of the signal probe, and a cable supporter which includes acable supporting block, the cable supporting block including a cableaccommodating hole for accommodating the coaxial cable therein toprovide the electric contact with the lower end of the signal probe,wherein the cable supporting block comprises a cable supporting recessrecessed from a surface opposite to an area where the cable supportingblock is coupled to the conductive block, wherein the coaxial cable issecured in place with adhesive filled in the cable supporting recess andhardened.
 2. The test device according to claim 1, wherein theconductive block includes a shield island projected upwardly from anupper surface of the conductive block and configured to shield noisefrom the at least one signal probe accommodated in the conductive block.3. The test device according to claim 2, wherein the cable supportingblock comprises an extended plate portion extended laterally from thecable supporting block.
 4. The test device according to claim 2, whereinthe cable supporter comprises a cable supporting substrate whichincludes a through hole through which the cable supporting block isinserted for coupling.